[A]ttempts to enforce by legal sanctions, acts obnoxious to so great a proportion of Citizens, tend to enervate the laws in general, and to slacken the bands of Society. If it be difficult to execute any law which is not generally deemed necessary or salutary, what must be the case, where it is deemed invalid and dangerous? And what may be the effect of so striking an example of impotency in the Government, on its general authority?
Talk of the "imperial decay" of your invalid port. "Its gracious withdrawal from perfection, keeping a hint of former majesty withal, as it hovers between oblivion and the divine Untergang of infinite recession."Stephen Potter
...my sister...was an interested and zealous invalid during sixty-five years, tried all the new diseases as fast as they came out, and always enjoyed the newest one more than any that went before; my brother had accumulated forty-two brands of Christianity before he was called away.mark twain
Sharia ... is, of course, invalid because it's God's Law, and God doesn't exist.pat condell
The invalid assumption that correlation implies cause is probably among the two or three most serious and common errors of human reasoning.stephen jay gould
You are not to disbelieve human science or think human reason invalid except when they venture outside their province.
The inherent contradiction between condemning the intellect as invalid and incapable of reaching truth, and using that same intellect to make the condemnation, seems, strangely, not to occur to those who hold this derogatory view of the intellect.
The Prophet passed by me at a place called Al-Abwa or Waddan, and was asked whether it was permissible to attack the pagan warriors at night with the probability of exposing their women and children to danger. The Prophet replied, "They (i.e. women and children) are from them (i.e. pagans)." I also heard the Prophet saying, "The institution of Hima is invalid except for Allah and His Apostle."
The oppressors alleged that Allah’s proof is invalid, and if we were permitted to speak out, the uncertainty would disappear.